UCLA/Getty Conservation Program

A graduate conservation training program focusing on the conservation of archaeological and ethnographic materials


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Project News: A comparison of block lifting materials and techniques

For the course “Science of Conservation Materials and Methods” offered in the Winter quarter of the 1st year, 3 students worked on a project which compared different block lifting materials and techniques. After a review of the literature on block lifting, they evaluated traditional and new approaches for block lifting fragile archaeological objects. For the first stage of the project they decided to test out different consolidants and facing materials for the objects they were going to lift, which were facsimiles of basketry, a corroded copper bracelet and a painted ceramic. After evaluating a group of eight consolidants and several facing materials, they decided on two consolidants (Paraloid B72 and cyclododecane) and two facing materials (Japanese tissue and cheese cloth) to try out during actual block lifts of the facsimiles. For the block wrapping materials, they tested a traditional wrapping material (plaster bandages) and two newer materials (Altraform and Varaform) to determine which was more effective at holding the block of soil together while lifting.

Area at the Getty Villa, behind the Ranch House, where the students did their block lifting experiments.

Area at the Getty Villa, behind the Ranch House, where the students did their block lifting experiments.

Robin O'Hern and Lily Doan excavate around the object to be lifted creating a block, or pedestal, of soil the artifacts sits on.

Robin O'Hern and Lily Doan excavate around the object to be lifted creating a block, or pedestal, of soil the artifacts sits on.

Facing a metal fascimile in preparation for block lifting

Lily Doan faces a metal facsimile in preparation for block lifting.

Nicole Ledoux and Robin O'Hern lift the now wrapped and supported block of soil out of the ground.

Nicole Ledoux and Robin O'Hern lift the now wrapped and supported block of soil out of the ground.

The block of soil has been lifted, flipped over on a board, and ready to be transported back to the lab to be further excavated. (In this photo: Lily Doan and Robin O'Hern)

The block of soil has been lifted, flipped over on a board, and ready to be transported back to the lab. (In this photo: Lily Doan and Robin O'Hern)

Robin O'Hern and Nicole Ledoux excavate one of the block lifted objects back in the lab.

A summary of their project and findings will be presented at the poster session of this year’s ANAGPIC conference, hosted by Queen’s University Art Conservation Dept. (Kingston, Ontario) May 22-24th. Stay tuned after the conference when their poster will be available on this site. You can see more images from this project at the UCLA/Getty Program’s Facebook page.


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Project News: The sampling of archaeological metals for Pb isotope analysis using EDTA

This poster was presented at the American Institute for Conservation’s 37th Annual Meeting held in Los Angeles, CA, May 19-22, 2009.

An alternative sampling method was investigated using ethylenediaminetetraacetic acid (EDTA) to extract lead (Pb) directly from an object for Pb isotope analysis to source archaeological metal artifacts. In order to perform the extraction, a group of objects from the sites of Kerkenes Dağ (Turkey) and Lofkënd (Albania) was soaked in a solution of EDTA and the Pb rich solution was then analyzed using time of flight inductively coupled mass spectrometry (TOF-ICP-MS) to determine the isotopic ratios present. In the archaeological literature success has been reported using this technique for the sourcing of majolica in the American Southwest and lead and silver objects in Pakistan. The authors in these cases reported no macroscopic alteration to the artifacts after soaking in the EDTA solution. However, no study has been undertaken to determine whether the extraction technique alters the surface of the object when examined under magnification.

Preliminary work was conducted by the authors in order to determine 1) whether or not this sampling technique could effectively be used for sourcing archaeological bronzes, in addition to silver and lead artifacts, from Anatolia and Albania and 2) whether soaking archaeological metals in EDTA causes any alteration to the surface of the objects.

Initial results of the Pb isotope analysis from the Turkish material indicated that EDTA solubilizes representatively for its accurate analysis. Examination of the objects in the field after extraction showed no observable change to the surfaces up to 45x magnification. Further work still needs to be undertaken to determine what surface changes or alterations to the object may be occurring during the extraction, since it is clear that material in addition to lead is being extracted out of the metallic artifacts. Based on these initial findings, however, EDTA extraction shows some promise as an alternative method of sampling metallic artifacts to the standard sampling methods used.

Poster-Sampling archaeological metals for Pb isotope analysis using EDTA

Poster-Sampling archaeological metals for Pb isotope analysis using EDTA